2645855521 has 2 divisors, whose sum is σ = 2645855522. Its totient is φ = 2645855520.

The previous prime is 2645855497. The next prime is 2645855543. The reversal of 2645855521 is 1255585462.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2365460496 + 280395025 = 48636^2 + 16745^2 .

It is a cyclic number.

It is not a de Polignac number, because 2645855521 - 2²³ = 2637466913 is a prime.

It is not a weakly prime, because it can be changed into another prime (2645855561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1322927760 + 1322927761.

It is an arithmetic number, because the mean of its divisors is an integer number (1322927761).

Almost surely, 2^2645855521 is an apocalyptic number.

It is an amenable number.

2645855521 is a deficient number, since it is larger than the sum of its proper divisors (1).

2645855521 is an equidigital number, since it uses as much as digits as its factorization.

2645855521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 480000, while the sum is 43.

The square root of 2645855521 is about 51437.8802148767. The cubic root of 2645855521 is about 1383.1057128878.

The spelling of 2645855521 in words is "two billion, six hundred forty-five million, eight hundred fifty-five thousand, five hundred twenty-one".